The proposed research is an attempt to further investigate the behavioral pharmacology of abused inhalants in mice utilizing two behavioral test procedures. More specifically. this research will attempt to address the current supposition that a majority of the abused inhalants produce a profile of neurobehavioral effects that are analogous to those produced by abused depressant drugs (e.g. barbiturates and alcohol). Two separate procedures will be employed to investigate the behavioral effects of inhaled solvents: 1) drug self- administration, and a novel 2) titration schedule. Drug self- administration is a paradigm that is used in the laboratory to ascertain whether compounds have reinforcing properties. Our intention is to develop a self-administration procedure with mice to evaluate the forcing properties of various solvents. Through the use of a second "titration scheduling" procedure. animals are trained through operant responding to adjust a stimulus. This is a technique that has been used quite frequently in behavioral pharmacology and will allow us to determine a solvent threshold for effects on operant responding.